CBUSH elements with non-coincident nodes
CBUSH elements with non-coincident nodes
(OP)
I have two parts (a skin and an aircraft former flange) overlapping with a row of fasteners along the length of the overlap modeled with CBUSH elements. The parts are modeled with CQUADs, and are slightly offset, such that the CBUSH elements have non-coincident nodes (though the CBUSH elements are in line with the axial direction of the fasteners). If I'm only trying to get fastener bearing and bypass loads from this model, is it necessarily a concern that the CBUSH elements have length? How would it change the result if the parts were flush and the nodes were coincident?





RE: CBUSH elements with non-coincident nodes
RE: CBUSH elements with non-coincident nodes
Just a little thing about CBUSH elements. If the two nodes of the CBUSH are not coincident you will have a fatal error. So mke sure that your nodes are coincidents.
Regards.
RE: CBUSH elements with non-coincident nodes
RE: CBUSH elements with non-coincident nodes
CBUSH is my preferred type of element, and not any problem exist for having non-coincident nodes. The CBUSH is a structural scalar element connecting two non-coincident grid points, or two coincident grid points, or one grid point with an associated PBUSH entry. As said above it has many advantages of using the CBUSH element over CELASi elements, for instance, if you use CELASi elements and the geometry isn’t aligned properly, internal constraints may be induced. The CBUSH element contains all the features of the CELASi elements plus it avoids the internal constraint problem.
In my opinion not any problem exist to have non-coincident grid points with CBUSH element. In any case I would suggest to make a pilot study and compare results, this is the way I run most of the times.
Best regards,
Blas.
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Blas Molero Hidalgo
Ingeniero Industrial
Director
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